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289 mm (11-318 IN.) 178 mm (7 IN.)
t 5.5 rnm (7/32 IN.)
Noise: Outputs:
Phono: measured at Mix bus output, at least 71 dB
below 10
mV input, 20-20 kHz. Measured at M67
output, noise depends upon M67 master gain control.
With M67 master gain at
"5%" (- 20 dB) noise output
of M67 will be -50
dBv maximum.
Line: will not add to noise of M67.
Distortion:
Program Channel: (measured at Mix Bus output)
Phono: Less than 1% THD with input level of 35
mV,
30 Hz-20 kHz.
Line: Less than 1% THD with input level of
+ 18 dBm, 30 Hz-20 kHz.
Monitor Channel: measured at
&ohm speaker output
with
Bohm load. Less than 1.0% THD with output level
of .56 volts to
8 ohms (40 mW) 100 Hz- 15 kHz. Less
than 2% THD with level of .31 volts at 40 Hz.
Control Interaction:
Under
1% dB with any control combination.
Inputs: Overload and
Shorting Protection:
Shorting the outputs will produce no damage. Overload
of phono inputs up to 3 volts will produce no damage.
Operating Voltage:
27 Vdc nominal supply from either internal supply
comprised of six
9V type 216 batteries or from the
associated M67 or M63 Audio Master. Minimum supply
is 21.5 Vdc; maximum is 35.0 Vdc.
Input
Clipping
90
mV
Over +16
d BV
(6.3 VRMS)
Over
+ 18 dBM (6.3 VRMS)
Over
+ 8 dBV (2.5 VRMS)
Corresponds
to
+I8 dBM output from M67
Input
Phono
Line Bridging
Line Terminated
Monitor
Input (via headphone plug)
Weight:
Without batteries: 2.38 kg (5 Ib, 4 oz)
With batteries: 2.61 kg (5 Ib, 12 oz)
Output
Clipping
Level
-
+ 17 dBV (7 VRMS)
Same as
M67
-2dBV (0.8 V;
80
mW)
Output
Mix Bus
Front-Panel
Headphone Jack
Rear-Panel
Headphone Jack
8-ohm Speaker
Output
CONTROLS, CONNECTIONS
AND OPERATION
CONNECTIONS (TO M67, M63 OR
SE30)
Stacking hardware is included for mounting the M67
or M63 on top of the
M675. See installation instruc-
tions for the
A68S Stacking Kit provided in the data
sheet covering mixer and circuitry accessories. The
stacking kit is not used with the
SE30. The plug on
the "Headphones" output cable at the rear of the
M675 is inserted fully into the M67, M63 or SE30
Headphones jack. The phono-type plug on the "Mix
Bus" cable at the rear of the M675 is inserted into the
'NOTE: The input impedance is set for 25k which is the correct load Mix Bus jack on the M67 or SE30, or High Level lnput
for a stereo cartridge operating with the L & R channels of the M63. The red and black "30 VDC" wires at the
parallel (monophonic mode). ~f an input impedance of 47k is rear of the M675 should be connected to the 30 Vdc desired, the 47k resistors (R226, R227) across the phono input connecfors on the M67, M63 or SE30. If rack mounting jacks may be removed. is desired, the M67 and M675 can each be mounted in
A68R rack mount accessories. The connecting cables
Minimum Common Mode Rejection:
on the M675 are of sufficient length to reach the M67
80 dB with line input of 10 volts at 100 Hz. in
this case.
lmpedance lmpedance
Designed
for Use With
Magnetic phono
cartridges
Less than
10 kilohms
600 ohms
M67 head-
phone jack Designed
For
Use With
M67 Mix Bus
(3.5k load)
or higher
600 ohms or
greater
Low
High (See
"Head-
phone"
section)
8 ohms or
greater
Actual
(Internal)
25
kilohms* +350 pF
75 kilohms t10%
600 ohms ?z 10%
1000 ohms
t 20% Actual
(Internal)
13 kilohms
t 20%
70 ohms
&lo%
5 kilohms k 20%
1.1 kilohms
-c 20%
4 ohms max.
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INPUTS
Line: The four line inputs (professional three-pin female
audio
connector+) are located on the rear panel and
designated "Line 1" through "Line 4." Inputs are
balanced (internal transformer,
mumetal shielded)
and connections are Pins 2 and 3 "hot," Pin 1
"ground."
Line 3 and Line 4 may be either 600 ohm line
termination or bridging, the choice being made by
the appropriate position of the "Bridge-Terminate"
switches above the Line 3 and Line 4 input connec-
tors. To obtain "Line" operation for the Line
1 and
Line 2 inputs, the corresponding "Line-Phono"
switch above the lnput 1 and lnput 2 controls on the
front panel must be in the "Line" position.
Impedances and operating signal levels are shown
in the "lnput Specifications" Section.
Phono: The two phono inputs (RCA type phono jack) are
located on the rear panel and designated "Phono
1"
and "Phono 2." To obtain "Phono" operation for the
Phono
1 and Phono 2 inputs, the corresponding
"Line-Phono" switch above the lnput
1 and lnput 2
controls on the front panel, must be in the "Phono"
position.
The nominal "Phono" input impedance is 25 kilohms
resistive, 330
pF capacitive. In order to change the
resistive input to 47 kilohms, remove the 47-kilohm
resistors at "Phono" input terminals
(R226, R227).
When phono inputs are not being used, both "Line-
Phono" switches should be left in "Line" to con-
serve battery life.
CONTROLS Individual lnput Gain Controls:
Front panel controls designated
"Input 1" through
"lnput
4" are the individual gain controls for corre-
spondingly numbered inputs. Note that the input
connectors are located on the rear panel directly
behind their corresponding control.
The lnput
1 and lnput 2 controls may be used to
control either "Line
1 - Phono 1" or "Line 2- Phono
2" inputs, respectively, depending upon the position
of the "Line-Phono" switch located immediately
above the lnput
1 and lnput 2 controls.
NOTE: The Line-Phono switches above Controls
1
and 2 are intended as SET-UP CONTROLS,
not operating controls. To conserve battery
life, these switches also control supply volt-
age to the phono preamplifiers. Hence, the
Line-Phono switches should not be thrown
while "on the air" unless the input controls
are both fully CCW
("0") to avoid introduc-
ing switching noise in the program material.
If phono inputs are not being used, both of
these switches should be switched to "Line"
to conserve battery life.
Monitor Gain Control:
This control is used to adjust the level of the front
panel monitor speaker, the front panel Headphone
jack, and the rear panel speaker jack. (See Cue
Operation below.)
tDesigned to mate with Cannon XL series, Switchcraft A3 (Q.G.) series or equivalent connector.
OUTPUTS
Mix Bus:
The Mix Bus output is a shielded cable extending
from the rear of the M675 cabinet and terminated
with a phono plug. This cable should be connected
to the "Mix Bus" jack on the back of the M67 or
SE30 (use the "Aux Level Input" on the
M63). Once
this connection is made, the four M675 input signals
will be added and mixed with the M67, M63 or
SE30 input signals.
Front Panel Headphone Jack: This jack provides both program and cue material to
600-ohm headphones. The "Monitor" control on the
front panel is used to adjust this headphone level.
The internal (or external) 8-ohm speaker is muted
when a plug is inserted into this jack.
Rear Panel
600 Ohm Headphone Jack:
This is a two-position jack for monitoring the output
of the M67, when the "Headphone" cable at rear of
M675 chassis is connected to the M67 "Headphone"
jack. The two-position phone jack is used to provide
a choice of level. Normally, a single circuit plug
should be used. If inserted only partially to the first
detent, the output level will be less than when
pushed fully in. If stereo phones are used, the
two-
position plug may be inserted fully and the output
will appear in both phones.
This jack is an extension of the two-level headphone
jack of the M67, and hence, it carries program
material only and its level is not controlled by the
monitor level control on the front panel.
While intended primarily for 600-ohm to
2-kilohm
headphones, this jack may be used with 8-ohm to
50-kilohm headphones, with resultant variation in
level. Crystal phones may also be used.
The "Tip" connections of the headphone plugs and
the two phono inputs are in phase with Pin 3 of all
input connectors on both the M675 and M67, and
with the tip of the Mix Bus connector.
Rear Panel 8-Ohm Output Speaker Jack:
This jack is for an 8-ohm high efficiency speaker or
for 8-ohm high quality headphones and provides
both program and cue material. The internal speaker
on the front panel is muted when the phone plug is
inserted into this jack. Use of the front panel
headphone jack, in turn, will mute
the internal (or
external) speaker. A mono (2 circuit) plug should
normally be used. If a stereo (3 circuit) plug is used,
external muting of the internal speaker is possible.
See schematic.
Monitor Speaker:
The internal speaker is activated unless either the
external
&ohm Output Jack or the front-panel 600-
ohm Headphone Jack is used. It monitors both
program and cue material.
OPERATION
Cue Operation:
The M675 "lnput" controls are in the Cue position
when rotated fully counter-clockwise and past the
detent.
With no M675 lnput Controls in the "Cue" position,
the monitor amplifier receives a program feed via
the connection to the M67 headphone output. The
